Biocompatibility of mineral trioxide aggregate flow and biodentine.

AIM: To evaluate the influence of powder-to-gel ratio (0.19 g powder to 50 µL of gel, thick MTA Flow, and 0.06 g powder to 50 µL of gel, fluid MTA Flow) on biocompatibility of MTA Flow (Ultradent Products Inc., South Jordan, UT, USA, lot: 2015122901) and compare it with Biodentine (Septodont Inc., Saint-Maur-des-Fossés, France, lot: B18542A). METHODOLOGY: The materials were manipulated and inserted into polyethylene tubes for implantation in twenty rats. After 7, 15, 30 and 60 days, the specimens were removed and embedded in paraffin. Haematoxylin and eosin sections were used to count the number of inflammatory cells (IC) and fibroblasts mm-2 (Fb). In the Masson's trichrome-stained sections, the fibrous capsule thickness was measured; picrosirius red-stained sections were used for birefringent collagen quantification. The data were submitted to two-way ANOVA and Tukey test (P ≤ 0.05). RESULTS: A significantly lower number of IC and consequently higher number of Fb were observed in the capsules adjacent to thick MTA Flow at all periods, in comparison with other materials (P ≤ 0.05). At 60 days, the quantity of birefringent collagen was significantly greater in the tissue in contact with thick MTA Flow, when compared with fluid MTA Flow and Biodentine. CONCLUSIONS: Although thick MTA Flow induced a less intense inflammatory response, all evaluated materials are biocompatible because they allowed regression of this process after 60 days.

Identification of Colletotrichum isolates from Capsicum chinense in Amazon.

Chili pepper (Capsicum chinense) is a great economic important culture on the State of Amazonas, and it represents, approximately, a production of 1.9 thousand tons per year. It is one of the hosts of Colletotrichum genus in the North region of Brazil. The aim of the study was to differentiate and to identify isolates of Colletotrichum collected from C. chinense in Amazon. Molecular characterization, using RFLP-PCR, ERIC-PCR and ISSR, was carried out initially for screening of morphologically similar isolates. Furthermore, phylogenetic analyses were performed using combined regions: Actin (ACT), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) for the three isolates, INPA 2066, INPA 2286 and INPA 1858, plus superoxide dismutase (SOD2) for INPA 2066. We showed that the molecular markers were able to distinguish the isolates of Colletotrichum studied and these results were confirmed with the phylogenetic analyses, three different occurrences of Colletotrichum species (C. siamense, C. scovillei and C. brevisporum) causing anthracnose in C. chinense in the State of Amazonas. This study represents the first report of the species C. siamense and C. scovillei in this host in Brazil.

In vivo evaluation of the inflammatory response and IL-6 immunoexpression promoted by Biodentine and MTA Angelus.

AIM: To evaluate the inflammatory process induced by Biodentine and mineral trioxide aggregate (MTA) in rat subcutaneous tissues. METHODOLOGY: A polyethylene tube filled with Biodentine (n = 20) or MTA (n = 20) was placed into the dorsal subcutaneous of forty male rats; in the control group (CG; n = 20), empty tubes were implanted. After 7, 15, 30 and 60 days, the polyethylene tubes surrounded by connective tissue were fixed and embedded in paraffin. The number of inflammatory cells was estimated in HE-stained sections; numerical density of interleukin-6 (IL-6)-immunolabelled cells was also performed. The differences amongst the groups were analysed statistically by Tukey's test (P ≤ 0.05). RESULTS: A high number of inflammatory cells and IL-6-positive cells were observed at 7 days, in all groups; however, in the Biodentine group, the number of inflammatory cells and IL-6-immunolabelled cells was significantly higher (P ≤ 0.05) in comparison with the other groups at 7 and 15 days. In the capsules of animals from all groups, a gradual and significant reduction (P ≤ 0.05) of these parameters was seen over time. At 60 days, the capsules exhibited numerous fibroblasts and bundles of collagen fibres; in addition, the number of IL-6-positive cells was not significantly different amongst Biodentine, MTA and control groups. CONCLUSIONS: There was a significant regression in the inflammatory reaction in the capsules indicating, therefore, that Biodentine is a biocompatible material.

Impacts of stocking on the genetic diversity of Colossoma macropomum in central Amazon, Brazil.

Tambaqui (Colossoma macropomum) is the main fish species farmed on a commercial scale in northern Brazil. In view of the current scenario of Brazilian aquaculture, studies on the genetic improvement and reproductive management of captive tambaqui are crucial in identifying the genetic variability of broodstocks and devising management practices. Genetic diversity of three tambaqui broodstocks in western Amazon was evaluated using molecular markers. Fin samples were collected from 89 fish; 38 from Balbina, 30 from a hatchery in Rio Preto da Eva, and 21 from the experimental farm of the Federal University of Amazonas (UFAM). Ten primers were used for the analysis of diversity and genetic structure. Of the 152 bands produced, 146 were polymorphic. The proportion of polymorphic loci showed little variation among the three stocks. The lowest and highest rates were found in the Rio Preto da Eva (80.92%) and Balbina (85.53%) stocks, respectively. Heterozygosity (H) and Shannon (I) indices were similar among the stocks; the lowest values were found in Balbina (H = 0.279 and I = 0.419), and the highest in UFAM (H = 0.294 and I = 0.439). Following analysis of the genetic structure and relationship, the sample was divided into two groups, with the Balbina stock clearly deviating from the others. The results suggest that, to increase genetic variability, molecular information may be used instead of replacement of wild breeders. The groups characterized here can be used in genetic improvement programs with other tambaqui broodstocks from different areas of South America.

Agrobacterium tumefaciens-mediated transformation of Lasiodiplodia theobromae, the causal agent of gummosis in cashew nut plants.

Lasiodiplodia theobromae is a major pathogen of many different crop cultures, including cashew nut plants. This paper describes an efficient Agrobacterium tumefaciens-mediated transformation (ATMT) system for the successful delivery of T-DNA, transferring the genes of green fluorescent protein (gfp) and hygromycin B phosphotransferase (hph) to L. theobromae. When the fungal pycnidiospores were co-cultured with A. tumefaciens harboring the binary vector with hph-gfp gene, hygromycin-resistant fungus only developed with acetosyringone supplementation. The cashew plants inoculated with the fungus expressing GFP revealed characteristic pathogen colonization by epifluorescence microscopy. Intense and bright green hyphae were observed for transformants in all extensions of mycelium cultures. The penetration of parenchyma cells near to the inoculation site, beneath the epicuticle surface, was observed prior to 25 dpi. Penetration was followed by the development of hyphae within invaded host cells. These findings provide a rapid and reproducible ATMT method for L. theobromae transformation.

Histological and histomorphometrical evaluation of furcation perforations filled with MTA, CPM and ZOE.

AIM: To evaluate the biological response of the periodontium adjacent to furcation perforations in rat molars filled with Endo-CPM-Sealer (CPM), MTA-Angelus (MTA) or zinc oxide-eugenol cement (ZOE). METHODOLOGY: The pulp chamber floors of maxillary right first molar teeth were perforated and sealed with CPM, mineral trioxide aggregate (MTA) or ZOE; the left first molars, without any treatment, were used as controls (CG). After 7, 15, 30 and 60 days, fragments of maxilla were fixed, decalcified and embedded in paraffin. Sections were stained with H&E, Masson's trichrome and submitted to tartrate-resistant acid phosphatase (TRAP) reaction, used as an osteoclast marker. The width of the periodontal space, the numerical density of inflammatory cells and the number of TRAP-positive osteoclasts in the bone surface were measured, and statistical analyses were performed using analysis of variance and Tukey test (P ≤ 0.05). RESULTS: In all experimental groups, the greatest number of inflammatory cells was observed at 7 days, especially in the ZOE group. In this group, the intense inflammatory process was related to a significant increase (P ≤ 0.05) in the number of osteoclasts and, thereby, in an increase in the width of the periodontal space. At 60 days, no significant differences in osteoclast numbers amongst CPM, MTA and CG groups occurred; the periodontal space was also significantly reduced in the experimental groups in comparison with the initial periods. However, in the ZOE group, the periodontal space was significantly larger (P ≤ 0.05) in comparison with MTA-based materials. CONCLUSIONS: The periodontium adjacent to perforations filled with MTA and CPM exhibited clear evidence of re-establishment and thus better biocompatibility than ZOE.

Thermostatistics of overdamped motion of interacting particles.

We show through a nonlinear Fokker-Planck formalism, and confirm by molecular dynamics simulations, that the overdamped motion of interacting particles at T=0, where T is the temperature of a thermal bath connected to the system, can be directly associated with Tsallis thermostatistics. For sufficiently high values of T, the distribution of particles becomes Gaussian, so that the classical Boltzmann-Gibbs behavior is recovered. For intermediate temperatures of the thermal bath, the system displays a mixed behavior that follows a novel type of thermostatistics, where the entropy is given by a linear combination of Tsallis and Boltzmann-Gibbs entropies.

[Myocardial infarct and coronary fistula. A rare combination]. / Enfarte do miocárdio e fístula coronária. Uma associação rara.

We report an unusual case of a 39-years-old male patient, with previous inferior and anterior non Q wave myocardial infarctions, in whom the coronary arteriography showed an arteriovenous fistula between the left anterior descending coronary artery and the pulmonary artery, without any other coronary lesions. We make a revision of this disease and discuss the mechanisms of ischemia.